Velez et. al., U.S. Patent Publication No. US 20020025471A1 discloses a heater for a thermal battery whose chemistry is actually disabled at lower temperature and becomes active at higher temperature, the heater preferably implemented as wire wound around the cell. Kamenoff, U.S. Patent Publication Nos. US 20050017690 and 20060012342 and U.S. Pat. No. 7,327,122, describe a heater for the purpose of discharging a battery more efficiently.